Electronic devices are ubiquitous in modern life. Smartphones, laptops, tablets, data capture devices such as RFID and/or barcode scanners, remote controls, sensors and a variety of other electronic devices are now commonplace and used in a wide range of environments, including mobile, industrial and residential locations.
Most electronic devices include one or more assemblies, or sub-assemblies, of electronic components which are mounted within an enclosure. These assemblies and/or subassemblies (hereinafter collectively “assemblies”) can include circuit boards, displays, input devices, antennas, speakers, batteries, sensors, data storage components, etc. and the enclosure serves to provide a mounting framework to maintain the assemblies in place and in position with respect to one another.
The enclosure often also serves both to protect the assemblies from the surrounding environment (i.e.—to prevent water or foreign materials from contacting the assemblies and damaging them) and to prevent users from inadvertently contacting the assemblies, thus preventing electrical shocks and/or other undesired contact. Further, positioning the assemblies within the enclosure can ensure necessary spacing (such as for radio antennas) between the assemblies and a user or between the assemblies themselves.
Electronic devices can be exposed to undesired physical shocks due to impacts, drops, crushes, etc., (hereinafter collectively “shocks”) especially if the device is intended to be portable or handheld. In such cases, it is desired that the enclosure can survive the largest expected shock and also that the device continue to function after the shock. Devices which purport to have these capabilities are typically referred to as “rugged” or “ruggedized” devices.
One failure mode which can occur with electronic devices occurs because of temporary deformation (e.g. bending, twisting, etc.) of the device enclosure, due to a shock, which can break assemblies such as displays and/or circuit boards and which can cause relative movement between assemblies within the enclosure, leading to failure of electrical interconnections between the assemblies or other negative effects.
Conventional rugged device designs have focused on strengthening the enclosure of the device to enhance the ability of the device to survive shocks by attempting to prevent deformation (or breakage) of the enclosure. For example, the Mac Book Pro™ laptop computers sold by Apple™ are fabricated from an aluminum unibody enclosure and the Toughbook™ laptop computers sold by Panasonic™ can have magnesium alloy enclosures. Other designs can employ enclosures molded from impact-resistant plastics, or other reinforced and/or composite materials.
While such enclosures can survive shocks, and may not deform unduly, their rigidity can result in the energy of the shock being transferred to the assemblies within their enclosures, resulting in damage to those assemblies. Accordingly, some rugged designs also include features such as resilient bumpers formed on, or attached to, the exterior corners or edges of the enclosure to absorb some of the energy of shocks and, in some designs, assemblies which are particularly susceptible to shocks (such as display screens and/or disk drives) may be mounted within the enclosure via resilient mounts in another attempt to absorb shock energy so that it does not damage these assemblies.
While such bumper-equipped designs can better survive shocks, they suffer from disadvantages in that they typically increase the cost of the device, increase the weight of the device and often increase the bulk of the device.
It is desired to have an enclosure for electronic devices which allows for rugged devices to be constructed at a reasonable cost and where those devices can better survive shocks.